After four years at Owen's College at London University, William Barton Worthington was articled to his father, S. B. Worthington, who was then Engineer of the Northern Division of the London & North Western Railway. He then spent a year on the Carlisle Joint Station reconstruction works and a year as an assistant to Messrs. Blyth and Cunningham of Edinburgh on the Caledonian Railway works. In 1878 he was apprenticed resident engineer for the London & North Western Railway on new works in and around Manchester. He became an assistant to S. B. Worthington in 1883, and in 1886 was appointed Engineer of the Lancashire Division of the London & North Western Railway. In 1890 he became Assistant Engineer of the Lancashire & Yorkshire Railway, and was appointed Chief Engineer to the company seven years later. In 1905 he was appointed Chief Engineer of the Midland Railway. After his retirement in 1915, he practised as a consulting civil engineer in London. W. B. Worthington was elected President of the Institute of Civil Engineers in 1917 but was prevented by illness from taking up office. He was able to serve as President in 1921-2 and then served on the Council until November 1927. In 1923 he received an honorary degree of D.Sc. from Manchester University. He was also Chairman of the Engineering Joint Council in 1922-3, President of the Smeatonian Society of Civil Engineers in 1928, and a Member of the Institute of Mechanical Engineers (1897).